The invention is to an obstruction marker, and more particularly to a self-contained, self powered marker.
Markers are used to highlight structures when it is impractical to make them conspicuous by painting. Markers may also be used in addition to aviation orange and white paint when additional conspicuity is necessary for aviation safety. They should be displayed in conspicuous positions on or adjacent to the structures so as to retain general definition of the structure. They should be recognizable in clear air from a distance of at least 4,000 feet (1219 m) and in all directions from which aircraft are likely to approach. Markers should be distinctively shaped, i.e. spherical, cylindrical, so they are not mistaken for items that are used to convey other information.
Spherical markers are used to identify overhead wires. Markers may be of another shape, i.e., cylindrical, provided the projected area of such markers will not be less than that presented by a spherical marker.
The diameter of the markers used on extensive catenary wires across canyons, lakes, rivers, etc., should be not less than 36 inches (91 cm). Smaller 20-inch (51 cm) spheres are permitted on less extensive power lines or on power lines below 50 feet (15 m) above the ground and within 1,500 feet (458 m) of an airport runway end. Each marker should be a solid color such as aviation orange, white, or yellow.
Markers should be spaced equally along the wire at intervals of approximately 200 feet (61 m) or fraction thereof. Intervals between markers should be less in critical areas near runway ends (i.e., 30 to 50 feet). They should be displayed on the highest wire or by another means at the same height as the highest wire. Where there is more than one wire at the highest point, the markers may be installed alternately along each wire if the distance between adjacent markers meets the spacing standard. This method allows the weight and wind loading factors to be distributed.
An alternating color scheme provides the most conspicuity against all backgrounds. Mark overhead wires by alternating solid colored markers of aviation orange, white, and yellow. Normally, an orange sphere is placed at each end of a line and the spacing is adjusted (not to exceed 200 feet) to accommodate the rest of the markers. When less than four markers are used, they should all be aviation orange.
Lighted markers are used for increased night conspicuity of high-voltage (69 KV or higher) transmission line catenary wires. These markers are used on transmission line catenary wires near airports, heliports, across rivers, canyons, lakes, etc. Lighted markers should be recognizable from a minimum distance of 4,000 feet (1219 m) under nighttime, minimum VFR conditions or having a minimum intensity of at least 32.5 candela. The lighting unit normally emit a steady burning red light. They should be used on the highest energized line. If the markers are installed on a line other than the highest catenary, then spherical markers are should be used in addition to the lighted markers. (The maximum distance between the line energizing the lighted markers and the highest catenary above the lighted marker should be more than 20 feet.) Markers should be distinctively shaped, i.e., spherical, cylindrical, so they are not mistaken for items that are used to convey other information. They should be visible in all directions from which aircraft are likely to approach.
If lighted markers are installed on a line other than the highest catenary, then spherical markers should be used in addition to the lighted markers. The maximum distance between the line energizing the lighted markers and the highest catenary above the lighted markers should be no more than 20 feet. The lighted markers may be installed alternately along each wire if the distance between adjacent markers meets the spacing standard. This method allows the weight and wind loading factors to be distributed.
U.S. Pat. No. 4,885,835 describes a method of assembling a line marker. The marker illustrated is a spherical ball including two hemi-spherical shells that are joined together with the power-line extending though the assembled shells.
U.S. Pat. No. 5,224,440 describes a clamshell hinging marker for mounting on overhead lines. It is similar to the structure of U.S. Pat. No. 4,885,835, in that it is a spherical ball including two hemispherical shells that are joined together with the power-line extending though the assembled shells.
U.S. Pat. No. 5,351,032 describes a visual and audio warning system that is used on power lines and utilizes a plurality of colored warning balls with an RF transmitter within one of the balls.
U.S. Pat. No. 4,474,133 describes an aircraft warning marker that is suspended from a high voltage wire.
The invention is a self powered spherical marker that is mounted on a wire, such as a wire on power lines, support cables, and fences by extending the wire on which the marker is to be mounted line though opposite openings in the marker. There are two sets of opposite openings to allow the marker to be oriented so that solar cells mounted on the exterior of the marker face a southernly direction. A battery inside the marker is maintained in a charged condition by the solar cells and power led lights that flash intermittently so as to draw attention to the marker. Two halves of the marker are secured together by a pin-latch fasteners that are placed around a shoulder extending around the periphery of the marker.